Portable traffic sign

ABSTRACT

A portable traffic sign comprising a frame having a handle and a reflex reflecting plate which may be fixedly or more advantageously rotatably secured to the frame. For example, the portable traffic sign carried by a pedestrian crossing a street at night can give a positive warning to a driver.

United States Patent lnventor Appl. No.

Filed Patented Assignee Priority Yoshio Fukushima Tokyo, Japan July 7,1969 May 25, 1971 Kabushiki-Kaisha Ricoh Tokyo, Japan July 8, 1968 JapanPORTABLE TRAFFIC SIGN 3 Claims, 6 Drawing Figs.

U.S. C1

Int. Cl G021) 5/12 Field ofSearch 350/98, 19,

References Cited UNITED STATES PATENTS Murphy Bergen et a1. EngelmannPalmquist et a1. Reinholdt Lemelson.... Rowland Primary Examiner-DavidSchonberg Assistant Examiner-Michael J. Tokar Att0rneyBurgess, Ryan andHicks ABSTRACT: A portable traffic sign comprising a frame having ahandle and a-reflex reflecting plate which may be fixedly or moreadvantageously rotatably secured to the frame. For example, the portabletrafiic sign carried by a pedestrian crossing a street at night can givea positive warning to a driver.

PATENTEU M25191: 3580.659

INVliN'lOR. Y0sH/o FUKUJHIIVIA A 'I'TORNEYS' PORTABLE TRAFFIC SIGNBACKGROUND OF THE INVENTION The present invention relates to a portabletrafflc sign and more particularly a portable traffic sign utilizing areflex reflecting plate or plates.

When a pedestrian crossing a street wants to give a warning to a driver,the pedestrian generally raises hishand or carries a warning flag.However, the drivers find it difficult to recognize these signsindicated by the pedestrians at night and especially at the streetsinsufflciently illuminated so that the accidents tend to occur. Toeliminate this problem, there has been proposed a portable traffic signhaving rotating reflecting mirrors attached to both of the surfacesthereof for reflecting the light beams from the head lights of anautomobile, thereby giving a warning to the driver when a pedestrian,crossesa street. However, it is not ensured that the reflecting mirrorscan reflect the light beams from the head lights always ,to the driversand even when a convex reflecting mirror is used, the reflected lightrays are not directed toward the driversin some cases and the intensityof light reflected by the convex reflecting mirror is low as thereflected light rays diverge. i

In view of the above, the primary object of the present invention is toprovide an improvedportable traffic sign which can positively reflectthe light beams from the head lights of automobiles to the driversirrespective of the direction of the reflecting plate.

SUMMARY OF THE INVENTION In brief, the present invention provides anovel portable traffic sign comprising a reflex reflecting plateattachedto a frame having the configuration adapted to be easily carriedor handled by hand.

The above reflex reflecting plate may be a transparent plastic or glassso molded as to have an incident surface consisting of a large number ofspherical surfaces having a relative small diameter or radius ofcurvature and a reflecting surface consisting of a large number ofspherical surfaces having a diameter or radius of curvature larger thanthat of said spherical incident surface and being in concentric andopposed relation therewith.

The reflex reflecting plate may be a large number of transparent smallglass beads bonded to an adhesive layer applied to a supporting bodysuch as cloth or the like.

According to the present invention, the reflex reflecting plates of thecharacter described above are bonded with each other in back-to-backrelation and this assemblyis held in the frame.

According to one embodiment of the present invention, the above reflexreflecting plate assembly is fixedly secured to the frame whileaccording to another embodiment, rotatably secured to the frame. Thereflex reflecting plate of the character described above can reflectalmost all of the light rays incident thereupon at various angle ofincidence in the direction of their light source so that when theportable trafflc sign of the present invention that is carried by apedestrian crossing a street is directed at a right angle relative tothe direction of the street, he can give a positive warning to a driver.When the reflex reflecting plate is rotatably fixed to the frame, thereflected light becomes alternately intense and weak as a pedestrianrotates the reflex reflecting plate so that a more positive andeffective warning may be given to a driver.

The above and other objects, features and advantages of the presentinvention will become more apparent from the following description ofillustrative embodiments thereof with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of oneembodiment of a portable traffic sign according to the presentinvention;

FIG. 2 is a section view thereof taken along the line II-II of FIG. 1;

FIGS. 3 and 4 are for explanation of the principle ofa reflex reflectingplate used in the present invention;

FIG. 5 is a front view of another embodiment of the present invention;and

FIG. 6 is an explanatory view of a reflecting device thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, a portabletrafflc sign of the present invention comprises a reflex reflectingplate generally indicated by l and fixedly secured to a frame 2 and ahandle 3 extending therefrom. As best shown in FIG. 2, the reflexreflecting plate 1 consists of two transparent'members 4 and 5 eachhaving an incident surfacecon'sisting'of spherical surfaces 4:: or 511having a smaller diameter and a reflecting surface consisting ofspherical surfaces 4b or 5b having a diameter larger than that of thespherical surface 4a or 5a and being concentric therewith, that ishaving the common center with the opposing spherical surface. Thesetransparent members 4 and 5 may be bonded together by an adhesive agent6 in back-to-back relation. As the term implies, the spherical surfaces4b and 5b are adapted to reflect the light beams incident upon thespherical surfaces 4a and 5a passing through the members 4 and 5 whilethe aspherical portions 40 in FIG. 1 of the transparent members 4 and 5are so treated as to absorb the light incident thereto.

The unique function of the reflex reflecting plate 1 will be describedwith reference to FIG. 3 illustrating one reflecting element consistingof one pair of opposed spherical surfaces 4a and 4b. When the parallellight beams are incident upon the spherical surface 4a at an anglerelative to the vertical axis of this reflecting element, the light beampassing through the common center 0 isrincident at a right angle to thespherical surface 4b and reflected at right angle so that this lightbeam passes through the center 0 again and emerges from the sphericalsurface 4a in the same direction with that of the incident ray. Theoptical path of this light beam or ray will be referred to as opticalaxis" of the parallel beams described above. The light beams parallelwith the optical axis but spaced apart therefrom by a small distance isincident upon the spherical surface 4a, refracted and reflected by thespherical surface 4 at the intersection of the optical axis with thespherical surface 411. The reflected light beam is refracted again atthe spherical surface 4a and emerges therefrom along an optical pathwhich is symmetrical to-the optical path of the incident light beam withrespect to the optical axis. Thus, it will be noted that the reflexreflecting plate 1 has the unique feature ofreflecting the light beamssubstantially to the source of these light beams. For example, when thelight beams from the head lights of an automobile or the like areincident upon the plate 1, the light beams are reflected totheautomobile so that the driver can perceive these reflectedlight beams,that is the plate 1.

FIG. 4 illustrates a modification of a reflecting element of the reflexreflecting plate 1. The reflecting element is a glass bead 41 which isbonded securely to the adhesive agent layer 42 applied to a supportingmember such as cloth or the like. The surface of the adhesive agentlayer 42 is adapted to absorb all the light rays except those incidentupon the glass beads 41 and the interface between the glass bead 41 andthe layer 42 is adapted to reflect the light incident upon the glassbead 41 and passing therethrough. Such glass bead has the reflexreflectivity as described with reference to FIG. 3 so that the reflexreflecting plate 1 may be constituted by the supporting member having alarge number of glass beads 41 arrayed thereupon instead of thetransparent members 4 and 5.

FIG. 5 illustrates a rotating reflecting plate. A reflex reflectingdevice 52 whose both surfaces are reflex reflecting surfaces 52a isrotatably secured to a frame 51 through pins 52b and 520 extending fromthe device 52 coaxially of a handle 51a extending from the frame 51.Reference numeral 53 designates a bearing for holding the pin 52b while54 and 55, bearings for holding the pin.52c. A knurled operating ring 56is fitted over the pin 52c and is partially exposed out of an opening51b formedthrough the handle 51a. By rotating the ring 51b by a finger,the reflex reflecting device 52 may be rotated.

The reflex reflecting plate 52 consists of a large number of glass beadsbonded to an adhesive layer applied to the surface of a plate-shapedsupporting member. As described hereinabove, the surface of the adhesiveagent layer is adapted to absorb all of the light rays incidentthereupon except those incident upon the glass beads, and the interfacebetween the glass beads and the adhesive agent layer is adapted toreflect the light rays passing through the glass bead and incident uponthe interface. Thus, it will be noted that the reflex reflecting device52 has a function of reflecting the incident rays to the direction ofthe source of these rays. When the glass beads are arrayed in rows andcolumns as shown in FIG. 5, the light rays incident upon the device atthe maximum incident angle of 75 may be reflected to the direction ofthe source of these light rays. That is, as shown in H0. 6, even whenthe reflex reflecting device 52 is rotated about the center 52 throughan angle of 150 relative to the same parallel rays, they may bereflected to the direction of their source. The reflex reflecting device52 must be rotated further through an angle of 60 before the otherreflecting surface can reflect the light rays. That is this 60 is a deadangle, but since the reflex reflecting device 52 may be continuouslyrotated by the operating ring 56, the light rays may be reflected in thedirection of their light source almost continuously. Instead of theoperating ring 56, an electric motor or the like may be used so as toautomatically rotate the reflex reflecting device 52.

I claim:

1. A portable traffic sign comprising:

a handle;

a frame fixed to and extending from said handle;

a reflecting plate mounted to rotate within said frame on an axisparallel with and longitudinally bisecting said handle;

said plate formed on one side by a first plurality of reflectingelements mounted therein in side-by-side relation;

said plate formed on the other side by a second plurality of reflectingelements mounted therein in side-by-side relatron;

each reflecting element of said first plurality and said secondplurality of reflecting elements having an outer spherical surfaceadapted to allow a light beam to pass in an entrance path therethroughand having an inner spherical surface adapted to reflect said light beamin a return path common to the entrance path; and

said first plurality and said second plurality of reflecting elementshaving their inner spherical surfaces respectively bonded to each othersaid handle formed with an opening therein, a pair of pivot mountingsbeing oppositely located on said axis in said frame to provide therotation of said plate, one of said pivot mountings including a pinextending into said handle and having a part extending through saidopening, said part having a ring mounted thereon for actuating rotationto rotate said plate.

2. A portable traffic sign according to claim 1, in which the radius ofcurvature of each said inner spherical surface is greater than theradius of curvature of each said outer spherical surface in eachreflecting element.

3. A portable traffic sign according to claim 1, in which spacing isprovided between adjacent reflecting units, and said spacing is formedto absorb light beams incident thereon.

1. A portable traffic sign comprising: a handle; a frame fixed to andextending from said handle; a reflecting plate mounted to rotate withinsaid frame on an axis parallel with and longitudinally bisecting saidhandle; said plate formed on one side by a first plurality of reflectingelements mounted therein in side-by-side relation; said plate formed onthe other side by a second plurality of reflecting elements mountedtherein in side-by-side relation; each reflecting element of said firstplurality and said second plurality of reflecting elements having anouter spherical surface adapted to allow a light beam to pass in anentrance path therethrough and having an inner spherical surface adaptedto reflect said light beam in a return path common to the entrance path;and said first plurality and said second plurality of reflectingelements having their inner spherical surfaces respectively bonded toeach other said handle formed with an opening therein, a pair of pivotmountings being oppositely located on said axis in said frame to providethe rotation of said plate, one of said pivot mountings including a pinextending into said handle and having a part extending through saidopening, said part having a ring mounted thereon for actuating rotationto rotate said plate.
 2. A portable traffic sign according to claim 1,in which the radius of curvature of each said inner spherical surface isgreater than the radius of curvature of each said outer sphericalsurface in each reflecting element.
 3. A portable traffic sign accordingto claim 1, in which spacing is provided between adjacent reflectingunits, and said spacing is formed to absorb light beams incidentthereon.